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Official Journal of the Japan Wood Research Society

New impedance measurement system estimating cross-sectional moisture distribution in cylindrical bodies and electric network modeling

Abstract

This work aimed to measure the cross-sectional moisture distribution in a cylindrical body using a double-glass-tube model filled with water and to construct an electric network model that explains the effects of moisture distribution. A new impedance measurement system introducing an intermediate electrode was exploited. The electrode was used to segregate the target local current from the whole current in a cross section of a specimen. Three model cylinders with different moisture distributions were used, and absolute values of impedance and phase were measured over the frequency range 1 kHz to 1 MHz. By introducing an intermediate electrode, frequency responses of the impedance and the phase showed characteristic changes in the high-frequency range associated with the moisture distributions. The trends were simulated numerically by using electric network analysis. The proposed method enabled measurement of a selective current path in the cross section of a cylindrical body.

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Correspondence to Nobuo Sobue.

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Sobue, N., Doi, K. & Date, M. New impedance measurement system estimating cross-sectional moisture distribution in cylindrical bodies and electric network modeling. J Wood Sci 57, 395–400 (2011). https://doi.org/10.1007/s10086-011-1195-9

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  • DOI: https://doi.org/10.1007/s10086-011-1195-9

Key words

  • Impedance measurement
  • High frequency
  • Intermediate electrode
  • Moisture distribution
  • Electrical model